4 



INSECTICIDES 



STOMACH POISONS 



The stomach poisons are used against inseets which bite 

 out and swallow portions of the food plant (Fig. 1). Wliere 



Figure 1 



the nature of the pest permits their usage, it is generally more 

 desirable to employ this class of- sprays inasmuch as it is not 

 necessary to wait un til the insect attack is well under way to 

 make the application. The treatment may be made, and the 

 pest eoming later feed upon the poisoned tissues and die. As a 

 general practice it is best to be on hand with the spray pump 

 jnst as soon as the pests,are noticed, for usually the yonnger 

 the iñsect the more susceptible it is to treatment. 



ARSENATE OF LEAD.— This material is steadily gaining 

 favor regardless of the fací that it is from three to five times as 

 expensive as the oíd time standard, Taris green. lis action is less 

 rapid than many of the other stomach poisons, but to over bal- 

 ance this deficiency, it is absolutely with out caustic or burning 

 effect when applied to the most tender foliage, thus making it 

 especially adapted for use upon seedbeds; plants liable to be 

 destroyed by biting inescts; or plants too tender to allovv the 

 application of Paris green. The material is unequaled in adhe- 

 sive qualities. This fact however bars its use upon some plants. 

 such as for spraying tobáceo late in the season. 



